In the related art, there is a known robot system with which three-dimensional shapes of shallots that are randomly conveyed on a conveyor are measured by means of a three-dimensional sensor, and the position at which an adhesion pad attached to a distal end of a robot arm is made to adhere thereto is determined on the basis of the acquired three-dimensional shapes (for example, see Patent Literature 1).
The robot system of Patent Literature 1 is a system for cutting and removing root-hair portions and stem portions at two ends of bulb portions, which are the thickest portions of the shallots. With this robot system, in a state in which a bulb portion is adhered to the adhesion pad, the position at which the thickness is greatest in the three-dimensional shape for cutting the root-hair portion and the stem portion is identified as the bulb portion, and a site having a flat area equal to or greater than a predetermined area, in the vicinity of the identified bulb portion, is detected as an adhesion site.